Linearly polarized single-frequency fiber laser based on the Yb:YAG-crystal derived silica fiber

A linearly polarized low-noise single-frequency fiber laser was demonstrated by using a homemade 1.2-cm-long Yb:YAG crystal derived silica fiber. A maximum output power of greater than 60 mW was obtained with a signal-to-noise ratio of ∼80dB and a polarization extinction ratio of 27.8 dB. Additionally, the relative intensity noise was measured to be -145dB/Hz above 6.5 MHz. A frequency fluctuation of less than 20 MHz was also obtained. The output power was scaled up to 14.5 W with a one-stage all-fiber amplifier scheme with a slope efficiency of 56.4%.